Nu-Cable Cable Barrier Systems. INSTALLATION MANUAL TEST LEVEL-3 LOW-TENSION Version A

(1)

Nu-Cable™

Cable Barrier Systems

I N S T A L L A T I O N M A N U A L

T E S T L E V E L - 3 L O W - T E N S I O N

(2)

(3)

Nu-Cable™

Cable Barrier Systems

(4)

Nu-Cable™ Cable Barrier System System Overview v. 2014.09A Page A-2

I N S T A L L A T I O N C O N S I D E R A T I O N S

The entire manual should be carefully reviewed prior to construction to ensure proper installation of the Nu-Cable™ Cable Barrier System.

The Nu-Cable™ Cable Barrier System is a straight-forward barrier, which is easy to install and can be safely maintained with the information contained within this installation manual.

The initial installation run for any new crew will need to be trained by a qualified Nucor Distributor or Nucor Steel Marion, Inc. representative. It is also strongly recommended that the first run for any new installation crew be completely installed and tensioned before attempting to start other runs.

If there is ever any doubt about a part of the installation contact Nucor Steel Marion, Inc. at (800) 333-4011 or the appropriate Nucor Distributor immediately.

Distributor contact information is listed on the last page of the manual.

Nucor is not responsible for any certifications, licensing, or permits, such as

environmental impact, that may be required in order to complete installation of this or any roadside safety device.

S I T E C O N S I D E R A T I O N S

The initial layout for the Nu-Cable™ High-Tension System should be free of hazards, obstacles, and debris. The cross-slope should be 4:1, 6:1 or flatter Grading may be necessary.

It is important to note that the high-tension cable barrier cannot be installed within a range of

1’ (305mm) to 8’ (2.44m) from the bottom of a

(5)

Nu-Cable™ Cable Barrier System System Overview v. 2014.09A Page A-3

H I S T O R Y A N D D E V E L O P M E N T O F T H E

N U - C A B L E S Y S T E M

The Nu-Cable™ system was originally developed by SafeRoads, LLC in 2002. It was designed around the usage of a Marion Steel 4#/ft Rib-Bak®_{post in a 3-cable} configuration. There were three versions of the system: two low-tension and one high tension. The product names were Rib-Bak®_{Cable System, Modified Rib-Bak}® Cable System & the US High-Tension Cable System, respectively. All of the systems were tested using standard cable (non-"pre-stretched"). The US High-Tension Cable system could also be used with factory “pre-stretched” cable. Due to tensioning and temperature cycles, standard cable exhibits the same performance characteristics as “pre-stretched” cables over time. The ability to use standard cable allows for realization of certain economic benefits during installation & maintenance.

Nucor Steel Corporation purchased Marion Steel and Saferoads in July of 2005. Shortly thereafter, Nucor Steel Marion, Inc. renamed the products ‘Nu-Cable™’. The Nu-Cable™ product line utilizes the same Rib-Bak® _{posts, locking hook bolts} and/or hanger, to support the ¾” cable. The cable heights and method of support vary depending the local terrain and desired NCHRP testing level.

The Nu-Cable™ system has amassed an impressive track record of successfully re-directing errant vehicle since its first installations in Ontario, Canada & Winger, Minnesota in 2003. Nucor Steel Marion, Inc. has continued to develop the Nu-Cable™ system to meet the needs of its users. The Nu-Nu-Cable™ system can now be used in following applications:

 Low-Tension Applications meeting NCHRP 350 TL-3 o On 6 to 1 slopes

 With standard J-Bolts  With locking hook-bolts

 High-Tension Applications meeting NCHRP 350 TL-3 o On 6 to 1 slopes or shallower

 4# Rib-Bak® Line posts  3 or 4 cables

 Direct driven, Driven Steel Sockets, or concrete socketed o On 4 to 1 slopes or shallower

 Utilizing a combination of locking hook bolts & hanger  High-Tension Application meeting NCHRP 350 TL-4

o On 6 to 1 slopes

 Utilizing a combination of locking hook bolts & hanger The Nu-Cable™ system is eligible for reimbursement according to the Federal Highway Administration for use on the National Highway System under the following letters:

BARRIER TERMINAL

B-96, B-96A, B-167

B-183, B-184, B-184A, B-193 CC-76, CC-105, CC-105A

The NUCOR 4# Rib-Bak®_{U-Channel posts are an acceptable post alternate}

(6)

Nu-Cable™

Cable Barrier Systems

I N S T A L L A T I O N M A N U A L

S E C T I O N B

B A R R I E R O V E R V I E W

C O N T E N T S

(7)

Nu-Cable™ Cable Barrier System Barrier Overview v. 2014.09A Page B-2

L I N E P O S T O V E R V I E W

A string line should be set to aid in properly placing the posts and cables. Mark each run starting with the location of end treatments. Then mark the position for each cable line post to be installed according to project plans to meet required deflections. Please refer to project plans for job specific post spacing.

Please refer to the project plans and specifications to determine which post spacing is required for the installation. FHWA Memorandum dated July 20, 2007

recommends a maximum post spacing of 15’ 0” (4.6m) for all manufactures of cable barriers. Varying post spacing can also be used when necessary due to conflicts with utilities or culverts.

It is helpful to mark every 1000’ (305m)* when laying out the system to aid in turnbuckle placement as the cable is unspooled.

*Mark every 750’ (229m) if using standard cable.

L A Y I N G O U T C A B L E

The cable used in the Nu-Cable™ system is 3/4” diameter (19mm), 3x7

construction, galvanized cable. It weighs 0.857 lbs/ft, and is packaged in 2000’

or 3000’ (915m) per wooden reel. The empty reel weighs 260 lbs (118kg).

(8)

Nu-Cable™

Cable Barrier Systems

(9)

Nu-Cable™ Cable Barrier System Barrier Installation: Low-Tension v. 2014.09A Page C-2

S Y S T E M I N S T A L L A T I O N

The details included in this section are from the North Carolina Department of Transportation Standards. The State of North Carolina has pioneered the usage of cable barriers with installing over 750 miles in the past 25 years. These details are for reference only, and should not supersede any local regulations or specifications. Check with the project engineer for site-specific details & construction manuals. The Nucor Nu-Cable™ line post can be used in lieu of S3x5.7 I-Beam wherever shown in these details, when used within the barrier itself or terminal section. (Ref. FHWA Letter B-96) The breakaway anchor post & stub connection to the

(10)

(11)

(12)

(13)

(14)

(15)

(16)

(17)

(18)

(19)

(20)

(21)

Nu-Cable™

Cable Barrier Systems

I N S T A L L A T I O N M A N U A L

S E C T I O N D

L I N E P O S T F O U N D A T I O N S

C O N T E N T S

FOUNDATION OPTIONS ... 2

Option 1: Direct-Driven Line Post ... 2

Option 2A: Socketed Foundation, Concrete Footing ... 3

Option 2B: Precast Socketed Foundation, Concrete Footing ... 4

Option 3: Direct-Driven Steel Socket ... 5

UNEVEN TERRAIN ... 7

SOFT SOIL FOUNDATIONS ... 7

(22)

Nu-Cable™ Cable Barrier System Barrier Installation: Foundations v. 2014.09A Page D-2

F O U N D A T I O N O P T I O N S

CAUTION: The options shown below are examples of typical foundations for use in strong or weak soil conditions. They should not be assumed to be the only options available. If soil conditions at each installation

location are unknown or do not meet the minimum requirements for strong or weak soil as outlined in Section M, a geotechnical review by a

professional engineer shall be conducted prior to starting installation. The results of this evaluation shall determine foundation design at each

installation location.

Some states may require deeper foundations based on site conditions and performance needs. Check with your project specifications and details to be sure you are utilizing the appropriate foundation design and depth.

Option 1: Direct-Driven Line Post

Only TL-3 systems use the direct embedment method. The post used is a 72” (1829mm) Rib-Bak®_{Line Post with no soil plate required. Direct driven line posts} are driven into natural soil (NCHRP strong soil) using a preset string line to depth of 39” (991mm). The top of the line post should be 33” (838mm) above ground after installation.

When solid rock is encountered consult the state DOT’s recommended procedures for resolution. If the state DOT does not have a procedure for installing line posts installed in rock, drill a 4” diameter hole to accommodate at least 15” of the line post.

For example if first encountering rock at a depth of 12”, excavate out the

(23)

Option 2A: Socketed Foundation, Concrete Footing

The socketed method utilizes a steel or plastic socket set into a 12” diameter x 30” deep [305mm x 762mm] concrete footing. The socket depth is assumed to be in NCHRP 350 strong soil.

If rock is encountered which would prevent minimum embedment, please consult the state DOT’s

recommended procedures for resolution or contact Nucor for further information.

TEST LEVEL 3 & 4

13 GA 4” OD x 15” (2.41mm x 102mm x 381mm)

All concrete should be 3000 psi (25MPa) minimum and should cure for at least 7 days before tension is added to system.

The concrete foundation is strengthened with one #3 steel reinforcing ring and two #4 x 28” steel dowels (dowel length may vary upon foundation depth). The ring is inserted to a depth of 4”; the dowels are inserted to a depth of 2”. The dowels should be installed at approximately 25 degrees off center so that they are in line against oncoming traffic. The steel reinforcement does not need to be tied.

Use a socket insertion tool (see photo) to install socket after steel reinforcement has been placed. The top of the socket should normally be flush with the top of the foundation concrete. To prevent runoff debris from entering the socket, the

(24)

Option 2B: Precast Socketed Foundation, Concrete Footing

The precast line post socket follows the same detail as the standard socketed concrete footing.

Use a 12” diameter x 30” deep [305mm x 768mm] form. Some contractors have found that modifying a standard section of 12” steel culvert pipe works well as a reusable form. Place steel reinforcement as detailed on plan standard. Plumb posts and pour concrete.

Be sure to not leave more than 1” (25mm) of the line post socket exposed above the ground line. It is easier to plumb the line post socket with a post temporarily inserted in the socket. The back fill material needs to be strong soil compacted in

6” (153mm) lifts with a hydraulic tamper.

(25)

Option 3: Direct-Driven Steel Socket

Much like the direct driven post option, there is a direct driven-steel socket option that can be fitted for post-driving machines and does not require the use of any concrete. This socket allows for the use of a shortened post.

When solid rock is encountered consult the state DOT’s recommended procedures for resolution. If the state DOT does not have a procedure for installing line posts installed in rock, drill a 4” [102mm] diameter hole to accommodate at least 15” [381mm] of the line post.

(26)

Nu-Cable™ Cable Barrier System Barrier Installation: Foundations v. 2014.09A Page D-6 For uneven terrain where the potential exists for line posts to be pulled out

(27)

U N E V E N T E R R A I N

For uneven terrain (see picture below), where the potential exists for line posts to be pulled out of their sockets by the tensioning of the cable, set the socket in the concrete with no more than 1” (25mm) above ground level. After concrete has set, drill a 3/8” (10mm) hole as close to the base of the footing as workable. Install a 5/16” x 1 ¼” (8mm) Grade 5 or better bolt through the post to hold the post in place.

S O F T S O I L F O U N D A T I O N S

Refer to local guidelines for foundation requirements in soft soil conditions. In many cases with line post foundations in weak soil, or where the frost line is below 30” (762mm), the footing should be increased in the depth to accommodate local soil conditions. Some states have successfully utilized 18” diam. (457mm) x 36-48” (914-1219mm) concrete foundations.

Direct-driven steel sockets can be increased in depth to 48” (1219mm) in order to accommodate local soft soil conditions.

(28)

D E B R I S E X C L U D E R

(29)

Nu-Cable™

Cable Barrier Systems

(30)

Nu-Cable™ Cable Barrier System Barrier Installation: Fittings v. 2014.09A Page E-2

T U R N B U C K L E S

Turnbuckles are used to achieve the appropriate tension in the system. By using pre-stretched cable, turnbuckles are required to be installed every 1000’ (305m). If pre-stretched cable is used, the hardware must be 1”D (25mm) to approach the breaking strength of the cable. Note: More turnbuckles than the minimum amount may be used if conditions require this option. Some maintenance crews have

successfully used turnbuckles in place of cable splices.

In a TL-3 system, if using standard cable, install one turnbuckle per cable every 750’ (229m). When using standard cable, the attachment hardware may be ¾” (19mm) or 1” (25mm) diameter. If the length of the run is 750’ long (229m), install the turnbuckle near the middle.

There are two options for the turnbuckle style used. The Nu-Cable™ system can either be installed with:

TEST LEVEL 3 or TEST LEVEL 4:

Standard Turnbuckles and “Wedge-Style” Cable Fittings

It is not recommend putting turnbuckles directly above each other in the same section between two line posts (bay). They will be easier to tighten if they are staggered. If a turnbuckle

becomes positioned at a post, do not install a special hook bolt at this post. This should be allowed for only one cable per post. If a maintenance crew strongly desires to place all of the turnbuckle in the same bay, the result will have no

(31)

F I E L D A P P L I E D C A B L E A T T A C H M E N T

A N D W E D G E E N C A S E M E N T

Cable attachment hardware requires the wedge to be properly encased in the cable strands and seated into the casting to insure that the cable will not slip out of the hardware.

o The wedge must be seated into the cables such that the flutes in the wedge nest with the three x strands of the cable. If not properly aligned cable slippage is possible.

o The optimum seating for the wedge is such that there is 1” of cable is beyond the wedge. At a minimum, the wedge must be seated inside the cable strands such that the top of the wedge is flush with all three 7 x strands. If one strand of the three 7 x strands is not at a minimum flush, then the wedge needs to be reset.

o If slippage between the wedge and strands occurs reset the wedge deeper into the strands.

o It is acceptable for the wedge to protrude up to 1/4” from the bottom of the casting as long as the wedge has been seated properly. If the wedge protrudes more it must be reset.

During the initial installation process the three 7x strands should be set in the body of the casting such that the nut has just enough room to be inserted. This will help ensure that the wedge is seated below the three 7 x strands.

(32)

W E D G E I N S T A L L A T I O N

1. Some contractors choose to use a screw driver to open up the cable and separate the three 7 x strands in preparation for wedge insertion. Once the wedge is inserted into the cable it should be driven approximately 1 inch below the end of the cable.

2. Other contractors have chosen to insert the cable into the casting and twist the casting until the strands “pop open” inside the casting opening up the cable lay. The wedge is inserted into cable strands approximately 1 inch below the end of the cable. The casting is then twisted back so that the cable lay is returned to the initial position.

3. Other installation methods are acceptable as long as the wedge placement & cable engagement is correct.

F A C T O R Y O R F I E L D - A P P L I E D S W A D G E D

F I T T I N G

(33)

S Y S T E M S P L I C I N G

The use of a cable splice is not recommended in the Nu-Cable system. A turnbuckle should be used wherever cable sections are connected. As

inspection of a cable coupling is hindered by the closed body design of a standard splice, use of a turnbuckle is strongly encouraged.

(34)

S T A N D A R D T U R N B U C K L E

SHOWN WITH 1” THREADED ROD

Hardware Strength (Min):

(35)

C A B L E E N D – 1 8 ” V E R S I O N

C A B L E E N D – 1 3 ” V E R S I O N

Hardware Strength (Min):

(36)

C A B L E S P L I C E

(37)

Nu-Cable™

Cable Barrier Systems

(38)

Nu-Cable™ Cable Barrier System Barrier Installation: Checklist v. 2014.09A Page G-2

I N S T A L L A T I O N C H E C K L I S T

 Are all the cables positioned at the correct height?

 Are there irregular curves or joints where an errant vehicle might snag?

Is there evidence of corrosion or damage to the cable? The cable should

be scheduled for repair if either of these circumstances exists.

 Check to see that nuts are installed on the hook bolts.

 Check that there is enough thread at the cable connections to allow for

future tensioning or repairs.

 Is there sufficient soil behind the posts to prevent them from being

pushed out when the barrier is hit? Eroded or disturbed soil should be

replaced and compacted.

 Is the post spacing correct?

 Is there evidence of corrosion or damage to the posts? The posts should

be replaced if either of these circumstances exists.

 Is the grading and slope appropriate for the system to be installed?

 Is the grading consistent and has been completed correctly?

 Are there any storm drains, culverts or other obstructions that could

interfere with the barrier?

 Is there anything in front of the cable barrier that might cause a vehicle

to vault the barrier or make the barrier ineffective? Items to look for

include vegetation, rough ground, debris, or hard packed snow. These

items should be removed if present.

 Is there enough clearance between the barrier and the hazard for the

expected barrier deflection? Minimum clearance is dependent upon post

spacing.

(39)

Nu-Cable

®

Cable Barrier Systems

(40)

Nu-Cable® Cable Barrier System System Delineation v. 2014.09A Page J-2

D E L I N E A T I O N

System delineation is not typically supplied with the Nu-Cable® barrier system due to the wide variety of delineation specifications between states. Delineation should be installed as directed by the engineer.

The bonding surface must be relatively clean and dry. Contaminated surfaces should be cleaned with a 50-50 Isopropyl Alcohol and water mixture. Use a lint-free cloth. Substrate temperature must be above 50 degrees F for proper adhesion. Primer should be shaken well before using. Apply a thin, uniform coating to the bonding surface using the minimum amount that will fully coat the surface. Allow to dry completely before applying tape.

Remove backing from pressure-sensitive reflective sheeting and apply pressure by rolling or rubbing to ensure good contact.

NU-TEN TRIGGER POST (1) 2” x 12” HIGH

(41)

Nu-Cable® Cable Barrier System System Delineation v. 2014.09A Page J-3

P O S T C A P S

Optionally required based on project specifications.

(42)

Nu-Cable® Cable Barrier System System Delineation v. 2014.09A Page J-4 The Nu-Cable systems that use hangers and straps (TL3 for 4:1 slopes or TL4 for 6:1 slopes) have the line post inserted all the way to the top of the cover utilizing the top grooves.

(43)

Nu-Cable™

Cable Barrier Systems

(44)

Nu-Cable™ Cable Barrier System Appendix: Soil Testing (Barrier) v. 2014.09A Page M-2

S O I L T E S T I N G

This section includes information relevant to determining the soil density & conditions at a specific location. The processes and steps listed here are referenced throughout the manual to determine installation modifications to the system foundations required in order to maintain performance in weak, or soft, soils.

CAUTION: The options shown below are examples of typical foundations for use in strong or weak soil conditions. They should not be assumed to be the only options available. If soil conditions at each location are unknown or do not meet the

minimum requirements for strong or weak soil as outlined in Section M, a

geotechnical review by a professional engineer shall be conducted prior to starting installation. The results of this evaluation shall determine foundation design at each location.

In order to verify site soil as a particular soil using a DCP (Dynamic Cone Penetrometer) or SV (Shear Vane), please reference the following table and instructions:

Cohesive Soils

Description Su (kpa) Foundation Pile Depth NU-CABLE LINE POST

50 - 75 450mm ø x 900-1200mm (18”ø x 36-48”) *(As Specified Per Project Engineer) 76 - 125 300mm ø x 750mm (12”ø x 30”)

Cohesionless Soils

Description Phi (0) Foundation Pile Depth

30 – 41 450mm ø x 900-1200mm (18”ø x 36-48”) *(As Specified Per Project Engineer) >41 300mm ø x 750mm (12”ø x 30”)

Table 1

• Purchase the DCP equipment.

• Purchase the ASTM publication ASTM STP 399 (available at the ASTM website) that

describes the test procedure

• Submit that to the state or project engineer to make sure the tool is acceptable to them. • The manual shows a curve that correlates the blow count from the DCP to a Standard

Penetration Test (SPT) blow count. For native soil, a blow count of 15 (DCP) is

equivalent to a Standard Penetration Testing (SPT) blow counts of 10 blows per foot.

• Once the SPT blow counts are known, we can use them to calculate the undrained

shear strength (Su) of the cohesive soil as follows:

 Su (kPa) = Converted SPT blow count x 5 this is the units included in the

NU-TEN manual

 Or

 Su (ksf) = Converted SPT blow count /10

• If the blow count in the field is less than 15, then the foundations will have to be

increased because the soil will not qualify as stiff.

• Need to make sure whoever runs the test out in the field is familiar with the procedure.

It is very easy to make a mistake about procedure of using this particular tool. Whoever performs the test in the field will have to assume responsibility for the results.

• The test should be performed in one-foot intervals down to the design bottom

elevation. We are interested in the strength of the soil above (at depths of 0, 6 inches, and 2 feet) the bottom elevation because this is the soil that will provide lateral

(45)

Nu-Cable™

Cable Barrier Systems

I N S T A L L A T I O N M A N U A L

S E C T I O N N

A P P E N D I X : R E P A I R & M A I N T E N A N C E

C O N T E N T S

REPAIR & MAINTENANCE ... 2

Cutting Cables ... 2

Pavement Overlays or Resurfacing ... 3

Emergency Access ... 3

(46)

Nu-Cable™ Cable Barrier System Appendix: Repair & Maintenance v. 2014.09A Page N-2

R E P A I R & M A I N T E N A N C E

The Nu-Cable™ System, regardless of installation method, is very easy to repair after an impact. The longitudinal elements (the cables) of the barrier will rarely need to be replaced. Visually inspect the cables, and if necessary, use cable splices to replace damaged cable.

Damaged posts and hook bolts should be replaced.

In the case of driven posts, the damaged posts must be removed and ground repaired before driving a new post.

After all impacts, the system requires inspection and replacement or repair of damaged parts.

Cutting Cables

Although it can be done, cutting cables under tension should be done with caution. It is best to first release tension in the cables by using the turnbuckles if at all possible. A vehicle becoming entrapped in the system can create a higher-than-normal tension. In an emergency, the cables CAN be cut, by using great care, with an abrasive wheel saw. Make sure no one is near the cutting

point upstream or downstream. Use gloves and safety goggles and cut very

(47)

Nu-Cable™ Cable Barrier System Appendix: Repair & Maintenance v. 2014.09A Page N-3

Pavement Overlays or Resurfacing

Cable heights are critical to performance of the system. If the roadway has

experienced an overlay, ensure cable heights are correct, and that the slope to the barrier does not exceed the maximum allowed. For significant overlays, it may be necessary to install extra-height posts.

Where it is anticipated that future roadway construction will require increases in the roadway surface elevation, a pro-active solution is to install extra-height posts in the original installation to allow for vertical adjustment of the cables. This option is only available in Test Level 3 systems.

Emergency Access

A temporary crossover for emergency vehicles or temporary traffic control can be made at any location of the installed cable barrier by removal of the special locking hook bolts and/or cable hanger straps, thus allowing the cables to slacken. The number of posts necessary for removal depends on the tension and temperature, but normally 15-40 posts will be enough. The weight of the cable will provide enough slack for passing over with vehicles.

Materials for Maintenance

Your NUCOR distributor carries an inventory of replacement parts for the Nu-Cable™ System to facilitate quick repair of an impacted system. In addition, we recommend that DOTs or maintenance authorities keep a minimum quantity of repair parts on hand.

A general rule of thumb is to stock 2% to 4% of the total project, rounded up to the minimum order quantities (below).

Line Posts = 50 piece bundles Small Hook Bolts = 100 pieces

Large Hook Bolts = 50 pieces Cable Hanger & Retainer Strap

= 50 Bundles CRP/Trigger posts = 3 or 4 pairs Turnbuckles = 3 or 4 pairs Cable Anchor Ends = 3 or 4 pieces Cable Spool = 2000 ft.

(48)

Nu-Cable

®

Cable Barrier Systems

I N S T A L L A T I O N M A N U A L

S E C T I O N P

A P P E N D I X : C O N T A C T I N F O R M A T I O N

C O N T E N T S

(49)

Nu-Cable™ Cable Barrier System Appendix: Contact v. 2014.09A Page P-2

T E C H N I C A L S U P P O R T & S A L E S

Manufacturer

:

NUCOR Steel Marion, Inc.

www.nucorhighway.com

Corporate Headquarters Steve Conway District Sales Manager (800) 333-4011 ext. 260 Steve.Conway@nucor.com Mailing Address: 912 Cheney Ave. Marion, OH 43301 Manufacturer Representatives Mark Fellows

District Sales Manager (740) 321-1273 Mark.Fellows@nucor.com Mailing Address: 912 Cheney Ave. Marion, OH 43301 Chris Sanders

Inside Sales Representative (740) 383-9637

Chris.Sanders@nucor.com Mailing Address: